US2675304A - Briquetting - Google Patents

Description

April 13, 1954 I G. KOMAREK 2,675,304

BRIQUETTING Filed Aug. 4, 1950 2 Sheets-Sheet l Fig.1.

/27 0 {f f INVENTORI ATTORNEYS Patented Apr. 13, 1954 BRIQUET'IIN G Gustav Komarek, Chicago, Ill., asslgnor to Komarek-Greaves and Company, Chicago, 111., a corporation of Illinois Application August 4, 1950, Serial No. 177,756

This invention relates to the manufacture of nodules or briquettes, particularly useful as fuels. For instance, nodules or lu'iquettes ranging from one twenty-fourth ounce to eight ounces in weight suitable for stokers or shovel firing can be readily formed by this invention.

Y The primary object of the invention is to provide a briquette or nodule which is firm, hard and abrasion-resistant.

An equally important object of the invention is to produce a briquette without the use of, customary binders, reliance being had upon the natural binders present, for example, in bituminous and semi-bituminous coals and upon an improved method wherein the fuel particles are produced in a form whereby, in the press, they are oriented to have a natural interlocking relationship.

Bituminous or semi-bituminous coals usually contain one or more fossil plant residues which have been identified as resins, pollen, and peaty substances, 1. e., humus. I find that "these can be availed of to adhere the particles of the briquette or nodule without the necessity of the use of extraneous binders. That is, bituminous coals contain in their fossilized structure relics of plant life, that can be processed into binding elements when the coal particles are subjected to a highly concentrated pressure. Such binders act as a mucilage within the nodules or briquettes formed bythe rolls, and, assisted by the pressure, serve to bind the nodules or briquettes into firm, resistant bodies entirely satisfactory for shipping, storage and combustion. ,Many of these natural binders are readily recognizable by well-known methods, among which are the following:

(1) Humz'c tissue which has resisted the centuries of coal-forming processes.-Th is material, when it occurs during the application of my process, is hydrolyzed into a peaty paste and contributes to the binding power.

(2) Highly resinous plant remains-containing resin reservoirs or gum ducts-These resins, or gums, are softened in the course of my process and distributed mechanically throughout the body of finely divided coal under treatment.

(3) Pollen-In some coals, while there is no evidence of humic remainsnor yet of great quantity of resinous matter, analysis indicates the presence of residual pollen. This forms an adhesive paste with water the coal.

2 Claims. (01. 44- 10) An essential feature of the method of this invention consists in compacting and densifying the particles of the fuel mass whereby the same are deaerated and interstices between the larger particles are filled with smaller sized particles and water carrying one ormore of the above-men tioned natural binders. Also, the compacting or densifying, which is conducted between closely fitting corrugated rolls forms the particles into flake-like bodies having a shale-like structure, i. e., the briquette is substantially completely formed of such particles without appreciable quantities of air or water and the particles assume a natural arrangement in which they are tightly interlocked to enhance the action of the natural cementing agents.

For purposes of a more complete understanding of the invention I have illustrated in the accompanying drawings a preferred apparatus for carrying out the improved method which, how-- ever, may be carried out by other means.

Referring to the drawings:

Figure 1 is a diagrammatic view partly in section illustrating the complete method;

7 Figure 2 is an end view. in elevation of one of the densifying rolls; I

Figure 3 is a sectional View of one of the densifying rollstaken on line 33 of Figure 2 Figure 4 is an elevation of one of the densifying rolls partly broken away; and

Figure 5 illustrates in detail the manner in which the corrugations of the rotating densifying rolls are so closely related that the fuel particles are formed as flake-like bodies.

In carrying out the invention and referring particularly to Figure 1, combustible materials or fuel, notably, coal of bituminous, semi-bituminous and semi-anthracite varieties which has been previously broken up, and dried, is suitably fed to the hopper or bin 10. It isa critical feature ofthis invention that the moisture content of the coal fed to the bin [0 should not be above about 3%, and preferably is between about 1% and 2%. The coal is dried at temperatures up to about 200 F. tothe aforesaid free moisture content, and then at a temperature from normal atmospheric F.) to about F. and the moisture content indicated, is delivered to the bin; The presence of acritical amount of free water precludes loss of small coal particles in about to 12% will be ground to extreme fineness of colloidal size of about one-half micron up to 200 mesh. It is in the smaller size fractions of the mass that the binder-making ingredients will be found, namely, the humus,

resins and pollen. Following the hammer mill operation and as an optional step, the coal may besubjected to a rolling between plain rolls if. I

the hammer mill grinding does not produce .fine enough granules. Some coals require greater fineness than others, i. e., the hard coals require greater fineness.

It is desirable that the 'maximum particle size after comminutionin the hammer mill or hammer mill and plain rolls be no greater than 100 mesh, but a mesh size as coarse as mesh may be used in this invention with some coals. The coal body is composed of various elements of varying hardness. The effect of the intense comniinution in the hammer mill is to divide into the coarser size (100111881). or thereaboutl the :1

harder mineralize d coal elements, i. e., vitrain, durain, and hard components of the ash, while the softer elements, when present, i. e., fusain,

resins, humio matter, pollen, etc. are by the same action comminuted into much smaller particlesfrom 200 mesh down to the colloidal and near colloidal sizes. These small sizes are picked up by the watenmechanically, and without chemical action, in the case of the gums and resins,

and, in the case of-the humic bodies and pollen, hydrolyzed into pastes. "Ehis intense grinding action also serves most thoroughly to mix the fine water-carried particles amid and among the coarser harder particles. There is thus evolved an efficient binding material from vegetable residues in the'coal bodyr From the hammer mill 12 the coal drops into a conventional surge hopper I3 which is a chamber having both ends open. Through the bottom open end of the surge bin the broken fuel particles are delivered directly to the bight of a pair of rotating compacting and densifying rolls !5 which are shown in detailin Figures 2 to 5. These rolls have intermeshing corrugated surfaces l6,as illustratedin Figures 2 and 5, and-are distinguished from plain, pro-compression rolls heretofore used. The corrugated rolls l5 do exert a direct grinding pressure, as is the case with plain rolls, but, as illustrated in Figure 5, inaddition, simultaneously exert a compacting and deaerating effect by twisting, compressing and forming the particles as small flake-like bodies after the manner of shale formation. Theimportant result of this treatment and one which is absolutely necessary to produce a firm, hard and a brasion-resistant briquette is the unusually complete deaeration which is obtained.

As the coal is introduced to the bight of the corrugated rolls IE, it is'preferably, although not necessarily, subjected to steam having a temperature from atmospheric up to about 300 F., the steam being introduced through suitable nozzles H. This steam facilitates the densification and deaeration in that the steam further assists indriving out the air. A g.

The coal from the deaerating and compacting rolls i5 is discharged into a column I8 and this coal, as explained, is in the form of small flakelike bodies having the form of a shalefied structure. The shalefied bodies. are of about onefourth to one-eighth inch in thickness and may be of various areas.

Stated another way, the treatment in the intermeshing corrugated rolls, as distinguished from plain rolls, takes the ground coal in which there were millions of voids and produces a flaked product wherein the number of voids, relatively speaking, are reduced to hundreds. The use of the steam in the densifying action is optional but preferable sineeit adds a small amount of mois- 'ture to enhance the carrying efiect of the original moisture of the coal in dispersing the natural binders and, also in replenishing moisture which may have become lost. Moreover, the steam excludes air, as stated above, and in connection with the natural binders, such as humus and pollen, renders them more effective chemically to exert their adhesive action.

' In the column I8 the shalefied particles build up, as indicated in Figure 1, upon the conveyor structure 19. This conveyor structure is located at the bottom of the column and comprises two screw conveyors forming pressure feeders disposed in opposed relation which operate to di rect the fuel centrally so that it may pass from the column through the slot or discharge opening 2t disposed over the bight of a pair of briquetting rolls '2 i. The chamber or column it may have any desired height, about twenty to forty inches being satisfactory, and the flakes are fed to the column at a temperature from atmospheric up to 300 F., depending upon whether or not steam is injected through the nozzle H into the fuel supplied to the pre-compression or densifying corrugating rolls iii. The column I8 preferably extends about thirty inches above the screw feed l9 and, as explained, the delivery opening 29 of the conveyor structure is disposed so as to deliver the particles directly into the bight of the briquette rolls 2! of the press.

Referring to Figure 1, it will be appreciated that the rotation of the rolls iii of the press not only bights into the fuel delivered from the opening 20 of the column l8, but, as I have found, exerts an upward pressure on the body of fuel delivered through the opening 253. The provision of the column is substantially prevents objectional extrusion of the coal upwardly because a portion 22 of the fuel in the column lsalways remains substantially static. This forms a dense head of coal which exerts a pressure directly upon the portion of fuel 23 delivered to the center of the column by the conveyor structure 59, i. e., directly over the delivery opening 20 and the bight of the briquette rolls 2|. In other words, the relatively more dense column or head of fuel 22 above the delivery outlet opening 20 constantly resists the upward pressure exerted by the briquette rolls and causes the coal to pass uniformly opposed conveyors l9 downwardly into the bight. of the briquetting rolls and, at the same time,

the presence of this head excludes air fromthe particles fed to the. press. 5

If desired, .and it is usually, preferable, steam at a temperature of about 200'? F. to 300 F. is introduced 'tothe coal in the column through nozzles or jets. 24. Thissteamhas theeiie'ct of further eliminating air, .and of rendering the natural binders more immediately-active to adhere the particles in the briquetting rolls. The use of live steam at about 50 p. s. i. boiler pressure is further important in that it brings the coal to a good pressing temperature, eliminates the tendency to "clam shelling and also reduces dusting.

That the coal has been substantially deaerated is definitely indicated by the complete lack of explosive and cracking noises during briquetting or nodulizing in the press rolls 2|. Normally, in the briquetting operation noises are produced resembling machine gun fire. This is eliminated by the use of the intermeshing corrugated rolls of the pre-compression densifying and compacting step, and by the provision of the column l8 which provides for delivery to the briquette rolls 2! of a constant dense deairifled body of particles.

Furthermore, whereas the coal fed from the densifier to the chamber or column l8 had the voids reduced to hundreds, as indicated above, the briquettes produced from the flake-like particles, as described above, are substantially free of voids. Moreover, in the briquettes, the particles are arranged in natural interlocking positions whereby the briquette is hard throughout the particles are tightly bonded, not only by natural binders, but also by the interlocking of the particles.

The briquetting operation may utilize any suitable briquetting machinery, but, preferably, the operation is conducted with high pressure rolls, namely, a pressure of 20,000 pounds to 30,000 pounds p. s. i. The ability to form satisfactory briquettes and nodules, without extraneous binders, in a roll-type press constitutes a new departure in the art of briquetting. The resultant briquettes are firm, hard and abrasion-resistant. Where the natural binding agent in the nodules or briquettes consists largely of resins, the product grows stronger in storage, in much the same manner as linseed oil increases in strength with age and exposure.

Referring to Figure l, a flat bar 25 is positioned between the briquette rolls 2|, in the nip thereof, the purpose of which is to prevent two great a quantity of coal from being compressed between the rolls. As indicated, the bar is situated above the medium line or axis of the rolls and extends across the face width of the rolls.

As shown in Figure 1, the briquetting rolls are rotatably mounted in a housing 26 and the briquettes, as formed, drop upon a travelling conveyor 21 of any suitable character to discharge the briquettes to a suitable location.

The entire operation from the star feeder II to the conveyor 2'! is carried out under air tight conditions, and one or more air outlets or vents 28 are located in the closed system for instance, at the hammer mill, as shown.

Referring to Figure l, the entire apparatus is enclosed in an air tight casing or chamber 30 having one or more air vents 28 with the parts in vertical or superposed relation as shown. The bin l0, feeder H and mill I2 may or may not be enclosed in the housing, the bin and feeder being shown outside of the same and the mill within the housing 30. In any event, means of conventional character. are provided forcontinuously or intl'imittently supplying material to the bin I0 and it is thus deliveredby gravity to the other instrumentalities within the casing 30. The surge hopper portion I3 of the casing forms a passage or conduit for material from the mill 12 to the corrugated rolls l5and the column 18 forms a passage for material from the rolls IE to the press 2|. It will be noted that the parts are preferably positioned in vertical alignment, the bights of the rolls l5 and 2| and the opening in the passage or column I8 being in substantial alignment as shown The rolls 2| have mating briquette or nodule forming recesses 3| in their surfaces and the formed briquettes are shown at 32 which are removed away from the rolls by the conveyor 21 also located in the chamber 30 as shown.

The rotatable corrugated rolls I5 having intermeshing surfaces are shown in detail in Figures 2 to 5. Each roll is preferably cast as complete roll sections 33 shown in Figure 3 with corrugated surfaces 56 and connected together by transversely extending bolts, rivets or other suitable means 34 as shown in Figure 4 inwardly of the corrugated surfaces of the rolls. Wear and guard rings 35 are secured to the exposed end or side of each section 33 by bolts 36 as shown. The central bearings 31 of the sections are transversely spaced apart as shown in Figures 3 and 4 and each is provided with a key-way 31' in transversely aligned relation whereby each of the rolls may be keyed to a rotating shaft 318 shown in Figure 1. The various instrumentalities are driven in any suitable manner to provide a continuous or intermittent operation.

It is desirable with some types of coal to use wet binders. In such cases, lower briquetting pressures are employed. By wet binders is meant binders which are melted or melted and mixed in the presence of steam, i. e., the binder is made fluid so as to coat the coal particles. Tall oil or tall oil pitch in small percent is used, namely, one-half of 1% up to 3% on the dry weight of the coal. These binders are introduced and mixed with the fuel in the surge hopper or into the column !8 below the rolls [5 by any suitable means.

Also, binders, can be used which need not be the type requiring melting, in which event, the binder is mixed in with the coal before it is fed to the hammer mill. Pulverant binders of this type are coal tar pitch, petroleum asphalt, dry sulfite liquor, dry starch, etc. and molasses may be used also.

I claim:

l. The process of forming briquettes and nodules which comprises passing coal particles of about 30 to 200 mesh size containing natural fossil plant residues and having a free moisture content not in excess of about 3% through intermeshing corrugated rolls and thereby deaerating, densifying and forming the particles into flakelike shalefied bodies, and compressing masses of the bodies between rolls into briquettes.

2. The process of forming briquettes and nodules which comprises passing coal particles of about 30 to 200 mesh size containing natural fossil plant residues and having a free moisture content not in excess of about 3% through intermeshing corrugated rolls and thereby deaerating, densifying and forming the particles into flakelike shalefied bodies, forming the bodies in a vertical column having a portion thereof constantly more highly densified and deaerated and thereby creating a head, delivering the bodies from the ammaoa column directly td a press at a point beneath and Number! under pressure exerted by said head, and com- 1,493,667 pressing masses of the bodies between rolls into 1,987,358 briquettes. Y 2,016,639 7 5 2,162,989 4 References Cited mv'the file of 121115 patent. 2,234,644 V UNITED STATES PATENTS 2,236, 1 Number Name Date 3 874,167 Crow 4-, Dec. 17, 1907 932,041 Matthews Aug.24,1909 Number 1,347361 "Bibb July 20, 1920 501 049 Komark Sept. 26, 1922 Name 1 v Date Diers 4......; May 13, 1924 Bonnet 9.- Jan. 8, 1935 Komarek 1 1.. Oct. 8, 1935 V Zwoyer eta1..1- June 20, 1939 Herglotz m. 11 Mar. 11,1941 Herglutz... Mar. 25, 1941 Hummel 9 Oct 13, 1942 FOREIGN PATENTS Country 7 V 7 Date France w. ,.1v 1 Jan. 15, 1929

Claims (1)

1. THE PROCESS OF FORMING BRIQUETTES AND NODULES WHICH COMPRISES PASSING COAL PARTICLES OF ABOUT 30 TO 200 MESH SIZE CONTAINING NATURAL FOSSIL PLANT RESIDUES AND HAVING A FREE MOISTURE CONTENT NOT IN EXCESS OF ABOUT 3% THROUGH INTERMESHING CORRUGATED ROLLS AND THEREBY DEAERATING, DENSIFYING AND FORMING THE PARTICLES INTO FLAKELIKE SHALEFIED BODIES, AND COMPRESSING MASSES OF THE BODIES BETWEEN ROLLS INTO BRIQUETTES.

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